Aryloxypropionitrile and dye mixtures and dyeing hydrophobic fibers therewith



United States Patent ()fifice 3d M588 Patented Dec. 17, was

3,114,588 ARYLGXYPRQPHQNETRELE AND DYE MTXTURES AND DYETNG HYDRGEHUBIC FHIBERS THERE- WETH tlharles E. Lewis, Somerville, NJ assignor to American Cyananiid (Company, New York, N.Y., a corporation of Maine No Drawing. Filed Feb. 26, 1962, No. 175,804 12 Qlaims. (til. 8-93) This invention relates to new dyeing assistant compositions and a new method for coloring of hydrophobic synthetic fibers by a disperse dyeing method.

The problem of dyeing hydrophobic fibers has received much attention in recent years. The heart of the problem lies in the difficulty of inducing the dyestuff to transfer from the dyebath and evenly penetrate the fiber. Generally, known approaches have fallen into two categories: The application of extreme pressure and temperature, or the formulation of the dyestuff with a carrier composition containing a dyeing assistant which promotes the desired transfer and penetration of the dyestufi. The present invention provides an improvement within the latter category.

A large number of compounds have been tested as assistants in dyeing hydrophobic fibers. Most known assistants are less than ideal for the intended use. One of the most common impediments is their tendency to shrink the hydrophobic fiber during the actual dyeing step. This amount of shrinkage varies in proportion to the concentration of the dyeing assistant in the bath, and this in turn normally varies with the concentration of the dyestutf. When only relatively weak dyeings are required, low concentrations of dyeing assistant are employed and this keeps shrinkage within tolerable limits. When strong dyeings are desired, the use of dyebaths having high concentrations of the assistant are required, and the resulting shrinkage exceeds tolerable limits.

Another disadvantage attending the use of known dyeing assistants is their incompatibility, especially in the higher ranges of concentrations, with fibers which are subject to deterioration. This precludes their use in dyeing textile blends containing cellulosic acetate fibers, for example.

Of course, any assistant, even it effective in most significant respects, to be of commercial importance must also be relatively easy and economical to prepare in large quantifies.

It is an object of this invention to provide an improved effective method of dyeing hydrophobic fibers, and also the dyeing assistants useful therein.

According to one aspect of the present invention it has been found that hydrophobic fibers, even when blended with acetate fibers, can be rapidly dyed in level deep shades without excessive shrinkage by having in the dyebath as the dyeing assistant at least one aryloxypropionitrile of the Formula I:

R ArOCH2C lHCN wherein AI is a six-membered carbocyclic aromatic radical of less than three rings such as phenyl, biphenyl and naphthyl which may have substituents such as one or two alkyl groups of less than eight carbons, a halogen (e.g., chlorine) or a nitro group; and R is hydrogen or methyl. Suitable aryloxypropionitriles are inter alia: 3-(p-chlorophenoxy) propionitrile, 3-(m-bromophenoxy)propionitrile, 3-(p-methylphenoxy)propionitrile, 3-(3,4-dimethylphenoxy) propionitrile, 3-(p-nitrophenoxy) propionitrile, 3- (p phenylphenoxy)propionitrile, 3-(1-naphthyloxy)propionitrile and 3-(4-methyl-1-1-naphthyloxy)propionitrile. It is a critical limitation of the present invention that dyeing assistants for use therein cannot have the cyanoethyl radical directly on a ring carbon rather than on the phenolic hydroxyl group. Such compounds, e.g., l-cyanoethyl-B-naphthol and pcyanoethylphenol, are virtually useless in dyeing operations. This is indeed surprising, since known and widely employed dyeing assistants such as phenol, o-phenylphenol and p-phenylphenol are of the phenolic type and do have a free phenolic hydroxy group.

Practice of the present invention involves adding the dyeing assistant to an aqueous dyebath either before or after the fiber is introduced, and maintaining the immersed fiber at an elevated temperature (e.g., from F. up to as high as 300 F.) until the desired depth of shade is obtained. Alternatively, the dyestufi can be added to the bath after the addition of the dyeing assistant. In normal practice the dyeing assistant is dispersed as an emulsion throughout the dyebath. This is effected by the use of an emulsifying and/ or dispersing agent as will be hereinafter described.

It is an advantage of the present invention that the dyeing assistant can be used in a wide variety of ways: (1) The emulsifying agent and aryloxypropionitrile may be intimately mixed or dissolved and added to Water with vigorous stirring whereupon the dyeing assistant is emulsified. The emulsion is then ready for addition to the dye bath. (2) One component of the emulsifying agent may be dissolved in the aryloxypropionitrile and the other components dissolved in the aqueous phase, so that when the two are intimately mixed the emulsifier is first formed in situ, after which the nitrile is emulsified. An example of this type is the addition of oleic acid to the nitrile and triethanolamine to the aqueous phase. (3) The dye and emulsifying agent may be dissolved in the nitrile and then emulsified in the aqueous phase. (4) The dye and part of the emulsifying agent may be dissolved in the nitrile and then dispersed in the aqueous phase which also contains the remainder of the emulsifying agent.

In preferred practice, the dyeing assistant must be emulsified with a small quantity of the aqueous phase to form a uniform emulsion before it is added to the dye bath.

Suitable emulsifying agents are chosen from a wide variety of known oil-in-water emulsifiers. In some cases these are also dispersants and this eliminates the need for a dispersing agent. Among the useful ones may be named the following anionic and nonionic types: fatty acid esters of sorbitan or polyhydric alcohols (e.g., sorbitan trioleate, glycerol monostearate); fatty alkylolamide condensates; and polyoxyethylated fatty acids.

When required, the dispersing agent may be any conventional one as illustrated by the following:

Alkylarylsulfonates Alkylarylpolyether alcohols Alkylphenoxy [polyoxyethylene] ethanols Ethylene oxide condensates Polyethylene glycol esters Polyoxyethylene esters of mixed fatty and resin acids Polyoxyethylene ether alcohols The ratio of emulsifier to aryloxypropionitrile is determined by the efiiciency of the emulsifier and thus the lower limit of the ratio is the amount required to produce emulsification. This is readily determined by inspection to determine presence of an oil-in-water type emulsion.

Too high a proportion of emulsifier is best avoided, since excessive amounts interfere with fixation of the dyestufi onto the fiber. Eris effect is determinable in each particular case by preparing individual dyeings and noting the variations in dyeing intensity with variation in the proportion of emulsifier. The range of proportions which results in the most intense dyeings is correct for practice of the present invention. A numerical value may be assigned to the range of useful emulsifier to aryloxypropionitriie proportions, within the framework of the foregoing discussion. In general it is from 2.5:100 to 10:10() on a weight basis. In preferred practice it is in the more limited range of 4:100 to 6:100.

The concentration of dispersing agent can vary within wide limits. In fact, since many emulsifying agents are self-dispersing, none may be necessary. For use with emulsifiers which do not have this property, about 5 to l00%, and preferably to 40%, on the weight of the aryloxypropionitrile, may be required.

it is an advantage of the dyeing assistants of the present invention that they may be used in high concentrations based on the weight of the fiber to be dyed, without adversely affecting the fiber. The concentration actually used, however, will of course, depend on the desired intensity of dyeing. In general, the intensity of dyeings can be adjusted in either of two ways: the weight ratio of dyestnir to dyeing assistant may be set within the wide limits of 2:1 to 10:1; and/or the weight ratio of dyeing assistant to fiber may be set within the wide limits of 6:100 to 24:100. By proper adjustment of both variables, dyeings of any desired intensity may be readily obtained. y it is another advantage of the present invention that it is not limited to dyeing hydrophobic synthetic fibers with any particular class of dyes and improves the shade with a wide variety of dyes such as disperse azo dyes, vat dyes and other water insoluble sulfur dyes, azoic colors, nitro, thiazoie and arylrnethane dyes, and even organic pigments. Another important application of the present invention is to the so-called optical bleaching agents or brighteners, i.e., colorless compounds which fiuoresce blue under ultraviolet light, which are used in whitening fabrics. Typical examples are 4-rnethyl-7-diethylaminocoumarin and 4-methyl-7-dimethylaminocoumarin.

It is a further advantage of this invention that any hydrophobic fiber, whether alone or in a fiber blend, may be dyed thereby. This includes polyester fibers from terephthalic acid and polyhydric alcohols (e.g., ethylene glycol); modified cellulosics (e.g., cellulose acetate and triacetatc) polyacrylonitriles; superpolyamides; and acrylonitrile copolymers with polymerizable vinyl compounds (e.g., vinyl acetate).

The dyeing assistant of the present invention may be used with high temperature pressurized dyeing operations, which are known in the art. However, the usual commercial dyeing methods for hydrophobic fibers involve atmospheric conditions and temperatures up to the boil.

The present invention is further illustrated by the examples which follow.

Example 1 A dispersion of phenoxypropionitrile in Water having a concentration of 1 oz. per gallon of water is prepared as follows:

1.5 grams of 3-(p-phenoxy)propionitrile prepared by the reaction of acrylonitrile with phenol in the presence of sodium, is dispersed by dissolving it in a minimum amount of acetone and reprecipitating it by adding Water to a volume of 200 cc. To this is added 100 milligrams of 1,8-diamino-4,S-dihydroxyanthraquinone, an anthraquinone dyestuif.

A five-gram skein of polyester fiber is then entered and dyed for one hour at 200 F. After dyeing, it is rinsed in hot water and soaped for 10 min. at the boil in a solution containing 0.1% soap and 0.1% soda ash. The dyed skein is then rinsed in hot and then cold water and dried. The polyester fiber is dyed a bright blue shade. The shade obtained is six times stronger than the shade obtained if the nitrile is omitted.

Example 2 ?CH2CH2CN To 210 cc. of a mixture of cresols having 50% meta, 30% para and 20% ortho-cresol, is added 10 grams of potassium hydroxide. After heating to dissolve, 140 cc. of acrylonitrile is added. The mixture is heated at reflux until the reaction is complete. (About 24 hours at C.) When the reaction is complete, the mixture is drowned in 800 cc. of dilute (about 5%) sodium hyd-roxide solution. The oily product which separates with the aid of salt is isolated and washed with water until the washings are neutral. It is dried over anhydrous sodium sulfate. It is then distilled, the product distilling between 88 and at a pressure of 0.8-0.9 mm, being collected.

Example 3 l The following is mixed in a Waring Blendor:

1144 grams of the product of Example 2 2 drops of Span 85, a Sorbitan trioleate emulsifier 0.144 gram of lauryl sodium sulfate, an anionic dispersing agent 25 ml. water The carrier emulsion is added to cc. water. 100 mg. of 1,8-dihydroxy-4-anilino-S-nitroanthraquinone, an anthraquinone dye, is added and when dispersed, a fivegram skein of a terephthalate polyester fiber is added. The skein is dyed for one hour at 200 F. It is then rinsed and soaped and rinsed as described in Example 1. The fiber is dyed a bright blue shade. The shade is 7.5 times stronger than the shade obtained if no carrier is used.

Example 4 If, in the dyeing procedure of Example 3, the following dyes are substituted, the following shades are obtained on polyester fiber:

(a) 2-chloroaniline coupled to l-phenyl- 3-oarbethoxy-5-pynazolone Green Yellow. (b) 4-ch1oro-2-nitroaniline coupled to above pyrazolone Reddish yellow.

(0) Aminoazobenzene coupled to phenol Do. (d) Chinoline Yellow (from 3-rnethyl- 7,8-benzoquinoline condensed with monochlorinated phthalic anhydride) Yellow. (e) p-Nitroaniline coupled to N-methyl- N-ethylaniline Orange. (1) 1-acetylamino-4 hydroxyanthraquinone Do. (g) Safranine T, an azine dye (old Cl.

841) Red. (h) 2-(N-ethyl-N-cy-anoethylaminophenylazo)-6'-methylsulfonyl benzothiazole Red. (i) Rhodarnine B Blue-red. (k) 1,2-diamirno- 4,5 dihydroxyanthra- Violet.

quinone Blue. (I) Victoria Blue Base, (1.1. 729 Do. (121:) Brilliant Blue RCF, Cl. 961 Do.

(n) Copper tetramino phthalocyanine Green blue. (0) Vat Brown RR (Prototype 12 1) Brown. (p) Nigrosine, an azine dye Black.

Example 5 A mixture consisting of 21.6 grams of mixed tar acids (consisting of 40% phenol, 20% m-cresol, 20% xylenols, 10% o-cresol and 10% p-cresol) 2.5 cc. of benzytrirnethylammonium hydroxide and 14 cc. of acrylonitrile is heated at reflux until the reaction is complete (about 18 hours at 91-100 (1.). The reaction mixture is drowned in 400 cc. of water. An oily layer of product forms which is separated by decantation, and washed with water until the 'washings are neutral.

Example 6 if in the dyeing procedure of Example 3, the dyeing assistant used therein is replaced by that prepared in Example 5, and the rest of the procedure followed, a bright blue shade is obtained on polyester fibers. The shade is eight times stronger than no carrier is used in the dyeing.

Example 7 17.5 milligrams of the azo prepared by coupling 2- chloroaniline to 1-phenyl-3-carbethoxy-S-pyrazolone is fused with 175 mg. of Renex 25 (polyethylene esters of mixed fatty and resin acids) noni-onic dispersing agent and 87.5 mg. of lauryl sodium sulfate. 25 cc. of water are added and the mixture stirred and heated to the boil. Water is added to a volume of 200 cc., and then 3 cc. of an emulsion prepared by mixing 48 g. of the product of Example 5, 2 g. of Span 85, 5 g. of lauryl sodium sulfate in 45 ml. of water are added. To this dye bath is added a wet-out skein of spun polyester yarn derived from terephthalic acid. The dye bath is raised to 200 F. and the dyeing carried out for one hour at this temperature. The dyed skein is then rinsed in hot water, soaped at the boil, rinsed with water and dried. The skein is dyed a full bright green yellow shade.

Example 8 If the carrier of Example 2 is used in the form of an emulsion prepared as in Example 7 and dyed according to the dyeing procedure of Example 3 using polyester fiber and the dyestutf shown in the following table, the following shades are obtained:

Percent Dye Shade Dye used on Weight Obtained of fiber Michlers hydrol 1 Blue. Victoria Blue Base 0.5 Do. Malachite Green 0.5 Green.

6 (c) a dispersing agent; and (d) a material selected from the group consisting of disperse dyes, organic pigments and optical bleaching agents.

2. The composition or" claim 1 wherein the aryloxypropionitrile is phenoxypropionitrile.

3. The composition of claim 1 wherein the aryloxypropionitrile is cresyloxypropionitrile.

4. The composition of claim 1 wherein the aryloxypropionitrile is the reaction product of mixed tar acids and acrylonitrile.

5. The composition of claim 2 wherein the emulsifier is of the oil-in-water type and is present in a concentration of about 4 to 6%, and the dispersing agent is present in a concentration of about 10 to 40% on the weight of the aryloxypropionitrile.

6. The composition of claim 3 wherein the emulsifier is of the oil-in-water type and is present in a concentration of about 4 to 6%, and the dispersing agent is present in a concentration of about 10 to 40% on the weight of the aryloxypropionitrile.

7. The composition of claim 4 wherein the emulsifier is of the oil-in-water type and is present in a concentration of about 4 to 6%, and the dispersing agent is present in a concentration of about 10 to 40% on the weight of the aryloxypropionitrile.

8. A method of dyeing synthetic hydrophobic fibers which comprises immersing the fiber to be dyed into a dyebath containing a disperse dyestulf and an aqueous emulsion comprising:

(a) at least one aryloxypropionitrile of the formula R ArOOH2H-CN wherein R is a member selected from the group consisting of hydrogen and methyl; and Ar is a carbocyclic aromatic radical of less than three rings having substituents selected from the group consisting of up to two lower alkyl groups, a halogen group and 8. nitro group; (b) from about 2.5 to about 10% on the weight of (a), of an emulsifying agent; (0) a dispersing agent; and (d) a material selected from the group consisting of disperse dyes, organic pigments and optical bleaching agents and maintaining the immersed fiber at an elevated temperature until the desired level of dyeing is obtained. 9. The method of claim 8 wherein the fiber is a polyester fiber.

10. The method of claim 9 wherein the aryloxypropionitrile is phenoxypropionitrile.

11. The method of claim 9 wherein the aryloxypropionitrile is a cresyloxypropionitrile.

12. The method of claim 9 wherein the aryloxypropionitrile is a reaction of the product of acrylonitrile and mixed tar acids.

References Cited in the file of this patent UNITED STATES PATENTS 2,280,790 Bruson Apr. 28, 1942 2,943,973 Archer July 5, 1960 

1. AS A COMPOSITION OF MATTER A MIXTURE COMPRISING: (A) AT LEAST ONE ARYLOXYPROPIONITRIE OF THE FORMULA 